1. Field of the Invention
The present invention relates generally to a sound reproducing apparatus, and more particularly, to a sound reproducing apparatus for continuously deriving a sound signal reproduced from a sound recording media such as a tape at a speed at the time of recording in a special reproduction mode such as a so-called review reproduction, in an apparatus having at least a sound reproducing mechanism such as a video tape recorder and an audio tape recorder.
2. Description of the Background Art
In general, in an apparatus having at least a sound reproducing mechanism such as a video tape recorder or an audio tape recorder, there exists a special reproducing mechanism such as a review mechanism for accessing a desired position to be reproduced by reproducing a sound signal while traveling a tape having, for example, the sound signal recorded thereon at high speed in the direction opposite of the normal reproduction mode.
However, when the sound signal is reproduced by such a review mechanism, the sound signal is reproduced in reverse, so that the meaning of the sound can not be grasped. In addition, since the reproduced sound signal is time-base-compressed, the frequency thereof is high, so that it is more difficult to confirm the content thereof.
In order to solve this problem, a technique has been proposed in which in the above described review reproduction, a reproduced sound signal is stored in a memory at a speed proportional to a review reproducing speed, and after storing is completed, the reproduced sound signal is read out from the memory while being time-base-expanded to derive the same at the original speed, which is disclosed in, for example, Japanese Patent Laying-Open Gazette No. 45607/1984.
However, according to such a technique, derivation of the sound signal is interrupted while the reproduced sound signal is being written into the memory. Therefore, the reproduced sound signal is always written in a memory to and from which writing and reading can be performed in parallel at the speed corresponding to the tape speed while being read out from the memory in the order opposite to that in writing. However, since the writing speed of the reproduced sound signal is fast and memory capacity is limited, the period is shortened in which the reproduced sound signal read out from the memory is continuous. More specifically, the sound signal to be derived becomes a sound signal having many discontinuous portions. Thus, if the memory capacity is increased, this problem can be solved. However, there is an associated increase in cost as a result.